The electricity for the cruise control goes through fuse no. 14 in the fuse box. From there it goes to the cruise control switch. The cruise control relay is located above the fuse box in the dash.
Volkswagen has a dedicated cruise control tester, designated VAG 1466, which dealerships and repair garages plug into the system to pinpoint malfunctions. If replacing fuse no. 14 does not fix the cruise control, it is necessary to take the vehicle to a Volkswagen dealership or authorized repair shop to use the tester to diagnose the location and cause of the malfunction in the system.